Fuel drier



Oct. 9,-1928. 1,686,690

- M. FRlSCH I FUEL DRIER Filed March 14, 1927 4 Sheets-Sheet 1 I anpentoz Wm M 6 I 3563/ G-Howm Oct. 9; 1928.

M. FRISCH FUEL DRIER 4 Sheets-Sheet Filed March l4. 1927 Oct. 9; 1.628. 6 1,686,690

M. FRISCH FUEL DRIER Filed March 14, 1927 4 Shets-Sheet 4 I 4.9 .55 J] y @w G 'H I Patented Oct. 9, 1928.

UNITED STATES PATENT OFFICE.

MARTIN FRISCI'I, OF S T. LOUIS, MISSOURI, ASSIGNOR TO INTERNATIONAL COMBUS- TION ENGINEERING CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE.

FUEL DRIER.

Application filed March 14, 1927. Serial No. 175,025.

This.invention relates to fuel driers and,

more particularly to driers of the grid type wherein the grids are arranged for movement to assist in feeding the fuel to be dried through the drier.

Fuel driers of the grid type, such as that disclosed in the patent to Kreisinger, No. 1,564,361, December 8, 1925, have been quite successful in drying coal or other such fuel prior to pulverization. By utilizing indirect heat for drying the, fuel, the heating elements or grids are capable of serving the double purpose of drying the fuel at the same time that the fuel stream is broken up to permit the more ready passage of the gases through the fuel stream and the heater elements. I

In order to facilitate this breaking up of the fuel stream, and to secure a better and 2 more uniform feeding of the coals through the drier, it is proposed, as one of the principal objects of this invention, to so mount the heater elements, which are relatively stationary in the Kreisin er construction, that they will be permitted to oscillate through a small angle. Suitable mechanism is provided for imparting this rocking movement to the grid element's, say once in every two minutes, with the result that coals, such as fine and very wet slacks and screenings,

which would not ordinarily flow through the drier by gravity, are now fed therethrough in a more positive manner. Among other objects of this invention is the provision of a plurality of superimposed grid-like heater elements of substantially hollow cross section, through which, the dry-- ing. medium, preferably steam, may be passed, each of the grids being provided at its opposite ends with means for pivotally mounting the same.

A' still further obje t is the provision of means for oscillating all of the grids simultaneously, thus providing a limited shearing movement betweenthe grids and causing a positive feeding of the coal therethrough.

A still further object ofthe invention is the provision of a means for automatically imparting an intermittent rocking movement to the drier rids.

\ A stillfurther o ject is the provision of means for automatically interrupting the rocking or oscillating movement imparted to the grids when the mill feed is interrupted or lnterfered with for any reason.

Other objects and advantages relating to details of economy and construction will appear more fully hereinafter. A preferred embodiment of the invention is illustrated in the accompanying drawings forminga part of this invention, in which:

Fig. 1 is a side elevation of a portion of a drying and feeding apparatus constructed in accordance with my invention, the casing being broken away to clearly show the grids.

Fig. 2' is a fragmentary front view partly 2-2 of Fig. 1.

Fig- 3 is a top plan view and section taken on the line 33 of Fig. 1..

Fig. 4 is a fragmentary elevational view of the steam entering side of the drier. Fig. 5 is an enlarged elevation of the drivlng mechanism shown in Figs. 1 and 2.

Fig. 6 is a section through a modified form of driving mechanism, and

Fig. 7 is .an end elevation of Fig. 6.

Referring more particularly to the drawings, it will be seen that the casing 10 in which the drier grids 11 are located is provided at its lower end with a discharge or delivery hopper 12. The grids-11 which are stacked one above-theother in the form of superimposed spaced layers are each of substantially rectangular form (see Fig. 3) composed of intersecting hollow bars 13 and 14 terminating, respectively, in the hollow side and end bars 15 and 16. All of the bars are of preferably triangular cross section, the bar 14 being substantially coincident with the longitudinal axis of the grid and the transverse bars 13 being substantially uniformly spaced between the end bars 16.

The grids 11 are all substantially similarly constructed, thus considerably reducing the manufacturing costs thereof at the same time that the necessity for stocking different sizes and shapes of grids is avoided. It will also be observed that the grids are of a'length slightly less than the distance between the end walls of the casing 10, their width, however, being considerably less than the width 'in section, the section being taken on the line- Y of the casing, whereby said casing is divided into two chambers a and b, one to either side of the stack of grids. One of said chambers, in this instance the chamber a, is provided with an air or other gas inlet 10*, and the other with a gas outlet 10., there being communication between said chambers through the lateral passages 10 provided by vertically spacing the grids. The air or gas can be caused to flow into and from the casing by ment and in communication with the central bar 14 of each grid, which trunnions 18 may be cast integrally with the rids or otherwise secured thereto in any suita le manner. The grids 11 are arranged in the casing 10 in superimposed relation with the trunnions 18 thereof projecting through the apertures 17 the bearing blocks 19.

m the opposite end walls of the casing, the vertical spacing between these aperturesbeing such as to provide spaces between each of the superimposed grids.

Suitable bearing blocks 19 are provided for the projecting portions of the trunnions 18, these bearing blocks being supported in position, one above the other, by bolts 20 which pass through holes in the vertically extending angle member 21 which is secured to the outer surface of each end of the casing 10, the shanks of the bolts being received between grooves formed in the proximate edges of Vertically extending manifolds 22 and 23 are disposed at opposite ends of the casing 10, the manifold 22 being that through which the heating medium, preferabl steam, is introduced into the grids, an the manifold 23 being that through which the steam is exhausted. Each grid 11 is connected at either end to the inlet and exhaust manifolds by the connections 24 and 25, respectively, the latter slopin downwardly to fpermit a better and more eii ective drainage or the condensate, and the inner ends of all the connections 24 and 25 being disposed within the central bores of the trunnions 18.

It will thus be seen that suitable provisions have been made for permitting an oscillatory or rockin motion to be imparted to the grids 11, t c axis of oscillation of each grid bein substantially coincident with the longitudinal axis of each bar 14. In order to impart a substantially uniform rocking motion to all of the grids 11 simultaneously, each grid is provided with a pair of spaced lugs 26 projecting outwardly from one of the side bars 15 centrally of the opposite ends thereof, the several pairs of lugs being in substantial vertical alignment. A connecting member or rod 27 projects upwardly between the lugs 26 and is connected thereto by the transversely extending pins 28 in such manner that upon vertical reciprocation of the rod 27 a rocking movement will be imparted to all of the grids 11 about their longitudinal axes. Thus, it will be seen that there isa small shearing movement between grids which aids in moving the coal.

One form of mechanism for imparting rocking movement to the grids is that shown in Figs.- 1 and 2 and most clearly in Fig. 5. Referring to this latter figure, it will be observed that a motor 29 is employed for driving the worm 30, which latter, in turn, meshes with the ear 31 secured to the rotatably mounted s aft 32. Also fixed to the shaft 32 is the eccentric 33, the rotation of which effects a reciprocation of the connecting-rod 34. Suitably journalled in the standards 35 at the end of the mechanism which is away from the motor 29, is the transversely extending shaft 36, upon which is'loosely mounted a bell-crank 37. A toothed ratchet wheel 38, which is keyed to the shaft 36 at one side of the bell-crank 37, is engaged by a pawl member 39, pivotally connected to the upper arm of the bell-crank 37. It will be seen that as the connecting rod 34 is reciprocated, the pawl 39 will-successively engage the several teeth of the ratchet, the result being that with every stroke the ratchet wheel will be caused to move through a small arc. An eccentric 40, which is also keyed to the shaft 36, has imparted to it the intermittent or step -by-step movement of the ratchet wheel 38, this eccentric 40 being suitably connected toa rocker bar 41, the upper end of which is pivotally joined to the links 42 and 43, the latter being, in turn, pivotally connected to the vertically reciprocable rod 27 which is operatively associated with the grids 11.

he arrangement, in this instance, issuch that the intermittently operated ratchet wheel 38, through the eccentric 40 and rocker arm 41, causes the sides of the grids to oscillate slightly above and below the horizontal to efi'ect a more positive downward feed of the coals therethrough, the oscillations taking place in a large number of small jerks.

When the source of the fuel supply is interfered with or otherwise interrupted, some means should be provided to automatically interrupt the rocking action of the grids, and, for this purpose, there is employed a pneumatically controlled diaphragm mechanism 44 which operates to move the rod 45 when the mill supply is shut oil. This rod 45 is arranged to engage the free end of the pawl 39, and it will be seen that when the rod 45 is moved, it disengages the driving port 53. By means from the steam cylinder.

pawl 39 from the ratchet wheel 38, with the result that further rocking of the grids 11 is interrupted.

Figs. 6 and 7 show a modified form of rocking mechanism. In this case, a double acting steam cylinder 46 is employed, the piston rod 47- of which is pivotally joined as at 48 to the rocker arm 41. This piston rod is further connected through the cushioning springs 49 and 50 to an arm or lever 51' which is fulcrumed as at 52 to a suitably fixed supof a link 54, the lever 51 is pivotally connected to the rod 55 of a dash pot piston 56 which operatesin a cylinder 57 filled with liquid. Both ends of the cylinder 57 on either side of its piston 56 are interconnected by a'pipe 58 provided at the upper end thereof with a needle valve 59 for controlling the rate at which the liquid may move from one end of the dash pot cylinder to the other. A vertically movable valve 60, the rod 61 of which is also connected tothe lever 51 through a link 62, s disposed intermediate the steam cylinder 46 and the dash pot cylinder 57, this Valve controlling the admission and exhaust of the steam into and The steam, preferably high pressure steam, for operating the piston to cause vertical reciprocation of the piston rod 47 is admitted through the ports 63, only hausted through the port 64, the exhaust steam, if desired, being exhausted directly into the drier grids to augment the low pressure steam used for heating. Due to the controlling action of the needle valve 59, the speed of operation of the dash pot piston 56 and, hence, that of the steam piston may be governed as desired. with the result that the grids may be rocked at greater or less intervals of time. If desired, a balanced quick opening valve 65 may be employed for interrupting the action of the dash potand steam cylinder pistons, and, hence, the-rocking motion of the grids, this valve 65 being preferably controlled by an automatically controlled diaphragm as in the case of the mechanism shown in Fig. 5, orby a solenoid indicated one of which is shown, and 1s eximposed grid-like fuel, a plurality of generally by the reference numeral 66. Suitable guides 67, as shown in Fig. 7, are provided for insuring true vertical reciprocation of the piston rod 47, a crosshead 68, into which the upper end of the rod 47 is threaded, being employed for the purpose.

It is to be understood that, while coal has been mentioned as being the material for which this apparatus is especially adapted, the apparatus may be ust as readily adapted for use in drying and feeding various other materials.

From the foregoing, 'it will be seen that I have provided a mechanism whereby continuity of flow may be secured in feeding materials which would not flow by gravity without provision of an influencing agency.

What is claimed as new and useful is 1. In feeding and drying apparatus, the combination of movable heating elements arranged to provide a vertical conduit for the material to be dried, and means for imparting a step by step movement to said elements.

2. In feeding and drying apparatus, the combination of a drier composed of a stack of vertically spaced rockingly mounted heating grids providing a conduit for the material to be dried, and means for rocking said grids.

3. A drying and feeding mechanism for fuel comprising a casing, a plurality of supermembers located within said casing, each of said members being provided with intersecting hollow bars, means for permitting said members to be oscillated about the longitudinal axes thereof, and means for passing a heating medium through said hollow bars.

4. In a drying and feeding mechanism for superimposed grid-like members, each of said members being provided with intersecting hollow bars, and op-- positely extending trunnions at either end of each of said members, said trunnions being provided with longitudinal bores in communication with said hollow bars.

In' testimony whereof I have hereunto si edm name. gn y MARTIN FRISGH. 

